Serum IL-10 Identified as Prognostic Factor for Multiple Myeloma

Baseline serum levels of the inhibiting inflammatory cytokine interleukin-10 (IL-10) were predictive of prognosis in a group of patients with multiple myeloma, according to the results of a study published in the British Journal of Cancer.

“In multiple myeloma patients, the levels of serum IL-10 significantly correlated with clinicopathological features, such as poor performance status, high International Staging System stage, elevated LDH levels, and no complete response after chemotherapy,” wrote researcher Hua Wang, of Collaborative Innovation Center for Cancer Medicine, Guangzhou, China, and colleagues.

In the small study, patients with lower levels of IL-10 had improved overall response rate and better survival than those patients with high IL-10 levels.

“With respect to the pathological role of IL-10 in multiple myeloma, previous studies have reported that IL-10 induces both plasma cell proliferation and angiogenesis in multiple myeloma,” the researchers wrote. “Furthermore, experimental studies suggested that IL-10 plays an important role in induction of chemoresistance in non-Hodgkin lymphoma and thyroid cancer.”

Therefore, with this study, Wang and colleagues wanted to see if pretreatment serum levels of IL-10 could predict treatment resistance and disease progression in patients with multiple myeloma.

The study included 188 patients with symptomatic multiple myeloma who were treated between 2005 and 2014 at Sun Yat-sen University Cancer Center. All patients had serum IL-10 measured using ELISA kits.

The median concentration of serum IL-10 among patients was 167.19 pg mL^-1 compared with a median of 17.54 pg mL^-1 among a group of 10 healthy volunteers. The researchers identified the best cutoff value for IL-10 as 169.96 pg mL^-1 with an area under the curve of 0.747 (P < .001). Using this value, 48.9% of patients were classified as having high IL-10 and 51.1% were classified as having low IL-10 levels.

More than twice as many patients with low IL-10 levels were able to achieve a complete response compared with patients with high levels (26% vs 12%; P = .016). Patients with low IL-10 had an overall response rate of 79.2% compared with 53.3% for patients with high IL-10 (P < .001).

With a median follow-up of 23 months, patients with low IL-10 levels at baseline had significantly improved 3-year progression-free survival (69.3% vs 13.3%; P < .001) and 3-year overall survival (93.6% vs 51.9%; P < .001) compared with patients with high levels.

“In this study, we found that good treatment response [complete plus partial response] is a significantly favorable prognostic factor independent of the treatment regimens in multiple myeloma,” the researchers wrote. “Moreover, our result showed that the overall response rate was significantly higher in patients treated with bortezomib-based regimens than those with DVD [doxorubicin, vincristine, dexamethasone] regimen (75% vs 47.1%, P < .001). Higher overall response rate only brought about longer progression-free survival but failed to improve overall survival.”

A multivariable analysis showed that a serum IL-10 level of greater than 169.96 pg ML^-1 was a significant predictor of both progression-free and overall survival.

“All these data confirmed that serum IL-10 was closely correlated with treatment response and prognosis in multiple myeloma, implying a significant role for IL-10 in the pathogenesis and development of this disease,” the researchers wrote.